Strata control at the face with fully mechanized sub-level caving

The movement rules and structure characteristic of overlying rock and behavior in a sub-level face are studied by using in-situ measurements, equivalent material simulating test, FEM and mechanical analytical calculation in the paper. It is considered that the movement of overlying strata is a separation movement, and the height of the immediate roof caved has doubled. This paper presents a structural model of voussoir beam combined with semi-arch as the basic strata structure over the face, and analyses stability of the structure and interaction of two structures. According to analysis of relationship of "supporting-surrounding rock", the paper indicates the principle of selecting support types and feature of strata control in sub-level caving face. The research results in the paper have been applied in selecting and designing supports and strata control, and an obvious effect has been got in practice.